Dual-Pulse Pump for Enhancing Supercontinuum Generation

We present a numerical study of the interactions between two solitons that split from two picosecond pulses with different time intervals during supercontinuum generation in a photonic crystal fiber. We demonstrate the manner in which the soliton interaction evolves along the fiber and affects the dynamics of the soliton pair. The results show that spectral broadening can be attributed to interpulse soliton collisions. By selecting an appropriate time interval for the two pulses, the spectral bandwidth can be effectively extended. Using two closely spaced pumping pulses, each having a peak power of 100 W, the width of the supercontinuum (SC) spectrum is increased by a maximum of 232.2 nm (measured at
$-$
30 dB) compared with the spectral width obtained with a single pump pulse of the same peak power. This phenomenon based on two pump pulses with a short time interval can generate a wider SC spectrum.